The present invention relates to transportation seating for mass transit vehicles, such as intra and intercity buses, trains, subways and the like. More particularly, the invention relates to such mass transportation seating which includes a grabrail.
Heretofore, a fairly wide variety of seating configurations have been provided or proposed for mass transportation vehicles. Such multipassenger seating typically includes a frame or a structural member which defines seat and back portions. The seat and back portions may be covered by various materials, such as fiberglass, foam, cushioning and the like.
Transportation seats may include grabrails at the upper edge of the back portion. Grabrails perform multiple functions. For example, they assist passengers in entering or leaving the seat and provide a handhold for passengers standing in the aisle portion of the vehicle. Examples of previous mass transportation seats which incorporate grabrails may be found in U.S. Pat. No. 3,737,198, entitled RAPID TRANSIT SEATING and issued on June 5, 1973, to Barecki et al; U.S. Pat. No. 3,747,979, entitled CANTILEVERED SEAT FOR MOTOR COACH VEHICLES OR THE LIKE and issued on July 24, 1973, to Barecki; and U.S. Pat. No. 3,802,738, entitled CANTILEVERED SEAT and issued on April 9, 1974, to Tantlinger. The seats disclosed in these above patents employ tubular frame structures. The grabrails are secured to or inserted into the tubular frame members.
Grabrails, besides providing assistance to passengers, perform additional important functions. Grabrails which extend above the top portion of the seat serve to compartmentalize passengers in an impact situation. The passenger who is thrown forward during an impact will strike the grabrail with his head or upper body portion. This prevents the passenger from flying over the seat in front of him. Since grabrails are in a zone which could be contacted by the head of the passenger and can serve the compartmentalization function, certain standards have been adopted relating to the energy absorption characteristics of the grabrails. It is desirable that the grabrail absorb impact energy so as to reduce the deceleration forces imparted to the body portion which contacts the rail.
Various proposals have been made to provide an energy absorbing grabrail in mass transportation seating. Examples of such prior approaches may be found in U.S. Pat. No. 4,106,810, entitled GRABRAIL FOR TRANSIT VEHICLE SEATS and issued on Aug. 15, 1978, to Barecki; and U.S. Pat. No. 4,077,664, entitled SEAT WITH CUSHIONED GRABRAIL and issued on Mar. 7, 1978, to Harder. The grabrails exemplified by these patents incorporate a tubular core structure which is covered with a cushionable material.
The grabrail disclosed in U.S. Pat. No. 4,106,810 includes a rectangular, steel tubular member and a surrounding self-skinning urethane foam. The ends of the grabrail are secured to the uprights of the seat frame through suitable fasteners. The grabrail exhibits excellent energy absorption characteristics.
The grabrail disclosed in U.S. Pat. No. 4,077,664 incorporates a circular, metal tubular inner member which is surrounded or enclosed by an outer layer of resilient cushioning material. The grabrail includes depending end legs which are inserted into frame uprights of the seat back structure and secured by fasteners. The seat frame structure is covered by a plastic seat shell. To accommodate the grab bar, a top flange of the seat shell must be cut away to permit insertion of the grabrail and assembly to the seat.
Various problems have been experienced in the transit industry with respect to prior grabrail structures. The grabrails which have been covered with a resilient or cushionable material are subject to vandalism. The material may be cut, slashed or ripped. This vandalism, of course, necessitates repair or replacement of the grabrail. Since grabrail structures are typically inserted into frame portions of the seat, partial disassembly of the seat may be necessary to remove the grabrail. Further, the prior approaches to grabrail constructions, as mentioned above, have generally required cutting or notching of the seat to accommodate the rail.
A need exists for a transportation seat and grabrail which is resistant or immune to vandalism, which is easily secured to the seat, which eliminates the need for notching or cutting of the seat shell, which is easy to maintain and clean, and which has energy absorption characteristics.